Bathroom Ventilation

spud65

Got an extension built a couple of years ago and the builders only put in a extractor fan in the bathroom now the motor is gone on it, just wondering if I put a vent in the wall plus if I take out the extractor fan an got a vent for the roof tile and ran it from the roof to the ceiling would that be alright, the shower is used 3 or 4 times a week.

spud65

tred

spud65 wrote: »

Got an extension built a couple of years ago and the builders only put in a extractor fan in the bathroom now the motor is gone on it, just wondering if I put a vent in the wall plus if I take out the extractor fan an got a vent for the roof tile and ran it from the roof to the ceiling would that be alright, the shower is used 3 or 4 times a week.

spud65

Must be missing something, why dont you just replace the extractor. Probably a cheap one installed by builder.

spud65

if the vents will do the the job that will be sound, saves me having to replace/install a new one every few years.

BryanF

spud, small suggestion - get an extractor fan that is connected to a humidity sensor instead of the usual light or pulley option

Maudi

spud65 wrote: »

if the vents will do the the job that will be sound, saves me having to replace/install a new one every few years.

id replace the the fan...a vent only opening is fine for a bedroom where its just static air flowing back and forth...but the extractor fan is essential to take out moisture laden air from shower steam...

spud65

BryanF wrote: »

spud, small suggestion - get an extractor fan that is connected to a humidity sensor instead of the usual light or pulley option

any suggestions on which type to put in?

BryanF

pm sent

spud65

Maudi wrote: »

id replace the the fan...a vent only opening is fine for a bedroom where its just static air flowing back and forth...but the extractor fan is essential to take out moisture laden air from shower steam...

thanks maudi
very useful info, always thought just the vents were ok, now i have to get a fan for upstairs bathroom

spud65

BryanF wrote: »

pm sent

thanks a mill BryanF

tred

Good stuff. your going to save yourself so much hassle this route. Not sure what Bryanf sent u, but there are also new ones out there not with door type dampers on the front that open and close when fan is on/off. Meaning no cold draughts in the winter blowing in!

L driver

Bryan, could you pm me humidity fan details please?

BryanF

L driver wrote: »

Bryan, could you pm me humidity fan details please?

aren't you building a new house? why not MVHR???

L driver

going with localised units, so I still need good humidity fans for the bathroom and en suite.

L driver

got pm. Thanks.

BryanF

L driver, would you mind outlining your building design:

1. are you going with positive input or demand controlled ventilation?
2. how has this impacted your BER rating (maybe your working to 08 regs)?
3. what air-tightness level are you aiming for?
4. what heating system are you using?
5. and have you assessed how many more kw's are required over using the MVHR?

L driver

BryanF wrote: »

L driver, would you mind outlining your building design:

1. are you going with positive input or demand controlled ventilation?
2. how has this impacted your BER rating (maybe your working to 08 regs)?
3. what air-tightness level are you aiming for?
4. what heating system are you using?
5. and have you assessed how many more kw's are required over using the MVHR?

hello,
1 the localised units will have sensors, so I guess it is demand controlled.
2 BER only takes efficiency % for it's calcs, as far as I remember, these units are a bit more efficient than regular mvhr. I don't think the difference was notable.
3 I am aiming for passive levels, 0.6ach, but as it is a self build I am doubtful but I will post results here.
4I am going with a GSHP with UFH.
5No I have not.

I will post more details and my experience when I am a bit further down the road. My build is taking time. Sorry if my answers above seem short. Ask/criticize anything, I will give an honest answer, I am not one of these that say everything about their build or choices is perfect.

BryanF

L driver wrote: »

hello,
1 the localised units will have sensors, so I guess it is demand controlled.
2 BER only takes efficiency % for it's calcs, as far as I remember, these units are a bit more efficient than regular mvhr. I don't think the difference was notable.
3 I am aiming for passive levels, 0.6ach, but as it is a self build I am doubtful but I will post results here.
4I am going with a GSHP with UFH.
5No I have not.

I will post more details and my experience when I am a bit further down the road. My build is taking time. Sorry if my answers above seem short. Ask/criticize anything, I will give an honest answer, I am not one of these that say everything about their build or choices is perfect.

1. best to get some advice on this - as I understand it, a centralised unit is required also. PM me if there is a specific product you had in mind.
2. best to do your provisional BER now

fclauson

L driver wrote: »

hello,
1 the localised units will have sensors, so I guess it is demand controlled.
2 BER only takes efficiency % for it's calcs, as far as I remember, these units are a bit more efficient than regular mvhr. I don't think the difference was notable.
3 I am aiming for passive levels, 0.6ach, but as it is a self build I am doubtful but I will post results here.
4I am going with a GSHP with UFH.
5No I have not.

I will post more details and my experience when I am a bit further down the road. My build is taking time. Sorry if my answers above seem short. Ask/criticize anything, I will give an honest answer, I am not one of these that say everything about their build or choices is perfect.

LDriver - not good enough I am afraid

at 0.6ACH MHRV is critical and necessary for the health of the building and yourself.

Please read Part F building regs on ventalation - it will save you a LOAD of hassle later

sydthebeat

L driver wrote: »

hello,
1 the localised units will have sensors, so I guess it is demand controlled.
.

L driver wrote: »

2 BER only takes efficiency % for it's calcs, as far as I remember, these units are a bit more efficient than regular mvhr. I don't think the difference was notable.
.

efficient at what? MHRV efficiencies relate to heat recovery.
How does non heat recovery affect your head demand loads?

L driver wrote: »

3 I am aiming for passive levels, 0.6ach, but as it is a self build I am doubtful but I will post results here.
.

SAS who posts here is also a self build, achieved a q50 of 0.39, n50 of 0.32. So its very possible to achieve with attention to detail and educated and interested trades.

L driver

the units have heat recovery, CO2 and RH sensors. The interested trades can be the problem, but I am very happy with my air tightness work and especially the guy who installed the attic membrane and pumped the cellulose. I have to wait and see the results.
What mvhr and heat system did SAS go with do you know?

fclauson

Ldriver

just to clairfy - those individual vents are fine for a bathroom etc - but in a 0.6 ACH house you need to ventalte the corridors, bedroom, sitting room etc etc

Part F gives you the details - there is a certain requirment for each "wet" room and there there is an overall figure

For a new build I would up the Part F rate for the first while (depending on the time of year you build) to remove the x hundred litres of water from the cements and plasters (also change the filters a little more often in the first period)

Don;t skip on the ventalation unless you like watching mushrooms grow on the inside of your house :mad::mad::mad::mad:

BryanF

fclauson wrote: »

just to clarify

PM'd to say LD is proposing a product by 'an old conqueror (begins with a V) product.. not knocking it, but not convinced by it either. would like to see some data before passing judgement..

fclauson

Ventalation is about airflow through a property - prehaps I can compare MHRV with locally placed systems as to trying to cook a shepards pie by having bunsen bruners on a couple of corners or the pie hoping that the pie will get evenly cooked as opposed to having a whole oven which heats evenly, circulates the heat all the time and cooks from all sides

whowantstwoknow

Hi all,

Looking to replace old fans in bathrooms and would appreciate the recommendations given out earlier in the thread.

Note in one room the vent is on an external wall and the other is up through the ceiling and tubed out through the attic to an opening in the fascia.

Thanks
W.

Bowlardo

spud65 wrote: »

Got an extension built a couple of years ago and the builders only put in a extractor fan in the bathroom now the motor is gone on it, just wondering if I put a vent in the wall plus if I take out the extractor fan an got a vent for the roof tile and ran it from the roof to the ceiling would that be alright, the shower is used 3 or 4 times a week.

spud65

BryanF wrote: »

spud, small suggestion - get an extractor fan that is connected to a humidity sensor instead of the usual light or pulley option

tred wrote: »

Good stuff. your going to save yourself so much hassle this route. Not sure what Bryanf sent u, but there are also new ones out there not with door type dampers on the front that open and close when fan is on/off. Meaning no cold draughts in the winter blowing in!

Could one of you point me in the right direction...going to do up the bathroom in the neat future and was looking for some advice....only have access to the external wall but if you could send me on the details of what you ended up using and were they a success?

BryanF

goggle: mechanical extractor fan humidity Sensitive